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1.
锆合金被普遍用做核反应堆中的燃料包壳和结构材料。在反应堆运行时,堆功率的波动和水冷却介质的流动.使燃料组件及其它构件发生循环变形,在极端情况下出现破损。本文概述了堆内包壳循环变形的特点,并分析了锆合金的循环变形行为,疲劳裂纹的形核与扩展,疲劳寿命及影响疲劳寿命的因素。  相似文献   

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3.
Zr对Al-Zn-Mg-Cu系超高强铝合金力学性能的影响   总被引:4,自引:0,他引:4  
研究了Zr对Al-Zn-Mg-Cu系超高强铝合金力学性能和显微组织的影响,结果表明,合金的强度随着Zr含量的增加而提高,含Zr量为0.06%(质量分数)时延伸率出现峰值,添加Zr可抑制合金的再结晶,使合金组织细化,并使该合金的断裂机制由沿晶断裂转变为穿晶断裂,对于所研究的超高强度铝合金,Zr的最佳添加量为0.06%~0.14%。  相似文献   

4.
This paper describes the development and evaluation of thixoformable Al‐Li‐Mg‐based alloys performed at the collaborative research center SFB 289, RWTH Aachen. Scandium and zirconium were added to AlLi2.1Mg5.5 (A1420) with the aid of DoE (Design of Experiments), and precursor billets were manufactured by pressure induction melting (PIM). To evaluate the thixoformability of the synthesized alloys semi‐solid processed connecting rods were manufactured by the rheo container process (RCP). Subsequent heat treatment raised the mechanical properties to maximum values of tensile strength, 430 MPa, yield strength of 250 MPa, and an elongation to fracture of 13 %. The RCP process was designed for the special requirements of highly reactive alloys. The paper presents the remarkable property and process benefits of the semi‐solid processing of Al‐Li alloys.  相似文献   

5.
论述了目前几种主要固体储氢材料的研究进展,包括金属基合金材料(镁系合金、稀土系合金、钛系合金和锆系合金)、碳基材料(活性炭、石墨纳米纤维、碳纳米纤维和碳纳米管)、玻璃微球、配合物以及金属有机框架物。通过比较各种材料储氢的机理与方式、吸放氢的温度与压力、循环寿命,分析了其优缺点,并展望了固体储氢材料未来的发展趋势,认为开发安全稳定高效的复合储氢材料、实现固体储氢材料的工业化制备是未来储氢材料研究的新方向。  相似文献   

6.
含锆超高强铝合金的研究及发展概况   总被引:14,自引:0,他引:14  
近年来,含锆超高强铝合金蓬勃发展,获得了广泛的应用,回顾了含锆超高强铝合金的历史及发展过程,重点讨论了锆元素在合金中的形式及作用机理,并就当前工作的重点及研究方向提出了一些看法及建议。  相似文献   

7.
航空发动机钛燃烧及阻燃钛合金   总被引:6,自引:0,他引:6  
介绍了航空发动机钛燃烧事故,以及钛合金燃烧试验,阻燃性能测试方法和太合金在国内外的研究和应用,并对国内外后的发展提出了一些建议。  相似文献   

8.
本文介绍了近年来国外在铝锂合金生产,开发和应用等方面取得的进展,并与复合材料进行了对比。提出了尚待解决的问题和对今后发展的看法。  相似文献   

9.
The thermal diffusivities of uranium alloys were measured by the laser-flash method between room temperature and 448 K. In recent years, several UZrNb alloys have been studied by many researchers and it was shown that additions of niobium and zirconium improve the properties of uranium-based alloys. The purpose of this article is to summarize the thermophysical properties of two uranium alloys that have been studied by CDTN in a program of development of fuel for low-power reactors. The nominal compositions of the studied alloys are U4Zr6Nb and U3Zr9Nb. The results obtained by the original laser-flash method and by the mathematical model developed by the laboratory were compared to the literature data. The adaptive Monte Carlo method was used to obtain the endpoints of the probabilistically symmetric 95% coverage interval for estimates of the output quantities and its uncertainties.  相似文献   

10.
生物活性Ti合金材料的研究现状   总被引:2,自引:1,他引:1  
Ti合金作为生物植入材料已应用于医学领域。综述了国内外Ti合金生物材料研究领域的最新进展,包括生物活性材料的微观特性、Ti合金表面改性和生物相容性。  相似文献   

11.
Magnesium – future material for automotive industry? Magnesium alloys show a very high potential in automotive applications as constructive metal, whereas the main focus lies on die cast parts. Electronic industry is the major commercial consumer for die castings besides the automobile industry. Room temperature applications like steering wheels and frame components in cars as well as mobile phone‐ or notebook housings are well established. These castings are produced with AZ‐ or AM‐magnesium alloys, which show good room temperature properties and a good castability. The great alloy development challenge in extending the use of magnesium cast alloys are application for higher temperatures. The application in powertrain components is considered to be the benchmark here. Besides alloy development there are also further research activities in development of casting processes. Semi‐solid processes like New‐Rheocasting (NRC), Thoxomolding ? or Thixocasting (TC) are adapted to the requirements of newly developed alloys. Not only cast alloys but also magnesium wrought alloys have moved to the centre of interest in the last decade. Alloy development for improving the formability on the one hand as well as process development in extrusion or rolling has to be done in order to find optimum parameters for deforming magnesium alloys properly.  相似文献   

12.
医用钛合金及其表面改性   总被引:12,自引:0,他引:12  
目前钛合金被广泛应用于医学领域,如矫形用种植体。简要综述了新型医用钛合金的开发以及钛合金表面改性提高其表面生物活性和耐磨性能的研究进展。  相似文献   

13.
轻水反应堆(LWR)是国际上多数核电站采用的堆型。锆具有良好的加工性能,优良的机械性能,较高的熔点、优异的耐蚀性能及核性能,被用作燃料包壳和堆芯结构材料,是发展核电及核动力舰船不可替代的关键结构材料和功能材料。随着核电技术的发展,对堆芯包壳材料性能提出了更高的要求,综述了核用锆合金包壳材料的国内外研究和使用现状以及新型SiC包壳材料的研发现状。总体来说,锆合金在未来几十年内仍是核反应堆包壳材料的主要用材,开展新合金的研发,不断提升锆合金的性能是世界各国研究者共同的目标;适时加大投入力度,强化条件建设,就能加快具有国内自主知识产权锆合金的产业化步伐,可最终实现核电及核动力用锆合金材料的自主化;SiC材料具有更高的熔点、更好的耐腐蚀性能,是一种极具应用潜力的材料,有可能成为第4代核反应堆的包壳材料,但还需投入大量研究。  相似文献   

14.
A K SURI 《Sadhana》2013,38(5):859-895
The area of materials research has registered a phenomenal growth in the recent years, assiduously accepting and assimilating ideas, concepts and analytical as well as experimental methodologies and techniques form almost all scientific disciplines, thereby demonstrating its remarkably multidisciplinary and interdisciplinary character. The focus of the materials programme of this centre is to provide materials, processes and processing solutions to the emerging needs of evolving indigenous nuclear energy systems by proactive research and development on a continuing basis. The initial stage of our activities was formulated around three stage Indian nuclear power programme. In stage I, material issues related to in-core materials with emphasis on development of fabrication routes of zirconium alloys for structural application were addressed. Subsequently the thrust areas were development and characterization of mixed oxide fuel, advanced zirconium alloys, structural steels, superalloys, neutron absorber materials based on boron carbides and borides, and shape memory alloys. The research was useful for in-service performance evaluation, safety assessment, residual life estimation and life extension of nuclear reactors built during stage I i.e., PHWRs and BWRs. It also included developments which would permit rapid expansion of nuclear power initially through fast breeder reactor based on mixed oxide fuel and later based on metallic fuels. For the 3rd stage, multi-layer coatings, graphite coolant tube, BeO, refractory metals and alloys, heat-treated zirconium alloys are being developed for CHTR, ADSS and AHWR. The materials being developed for fusion programme are low Z and high Z material for plasma facing application, Cu-alloys for heat sink, austenitic steels, RAFMS and ODS for structurals and NbTi, Nb3Sn and Nb3Al superconductors, lithium titanate, lithium silicate breeders, and Pb–Bi coolant. A brief overview of the materials research activities currently being pursued at Bhabha Atomic Research Centre is presented in this article.  相似文献   

15.
Zirconium‐based alloys are used in water‐cooled nuclear reactors for both nuclear fuel cladding and structural components. Under this harsh environment, the main factor limiting the service life of zirconium cladding, and hence fuel burn‐up efficiency, is water corrosion. This oxidation process has recently been linked to the presence of a sub‐oxide phase with well‐defined composition but unknown structure at the metal–oxide interface. In this paper, the combination of first‐principles materials modeling and high‐resolution electron microscopy is used to identify the structure of this sub‐oxide phase, bringing us a step closer to developing strategies to mitigate aqueous oxidation in Zr alloys and prolong the operational lifetime of commercial fuel cladding alloys.  相似文献   

16.
事故容错燃料(ATF)是日本福岛核事故之后提出的新一代核燃料概念,主要是为了提高反应堆在事故工况下的容错性能,从根本上提高核电厂对严重事故的抵御能力,从而有效地提高核电的安全性和经济性.针对传统核燃料使用的锆合金包壳,通过外表面涂层改性的方法提高其在事故工况下的抗高温氧化性能是事故容错燃料的主要研究方向.为了对锆合金涂...  相似文献   

17.
快速凝固铝硅合金材料及其在汽车中的应用   总被引:2,自引:0,他引:2  
本文介绍了快速凝固技术的特点及在高硅铝合金中的应用潜力,综述了快速凝固高硅铝合金的制取方法及研究现状,扼要总结了快速凝固高硅铝合金在汽车工业中的应用,最后提出这一研究领域中存在的问题及发展前景。  相似文献   

18.
叶青  栾佰峰 《材料导报》2011,(Z1):492-496
添加合金元素来提高锆合金的力学性能和耐腐蚀性能,近年来受到研究学者的广泛关注。概述了加钼锆合金的国内外研究现状和发展趋势,着重介绍了添加钼元素对锆合金力学性能、耐腐蚀性能、微观组织、形变织构、第二相等方面的影响。在锆-铌合金中添加适量的钼,再通过适当的热机械处理,可以得到高强度、耐腐蚀、晶粒细小的锆合金。  相似文献   

19.
锆的晶体结构是密排六方,其腐蚀各向异性比较显著。另外,锆合金在加工成材的过程中会产生织构,这将影响锆合金的耐腐蚀性能。论述了锆合金腐蚀各向异性的研究方法、结果和进展,并讨论了织构对锆合金耐腐蚀性能的影响,为认识锆合金的腐蚀行为、研究其腐蚀机理提供参考。  相似文献   

20.
高熵合金不同于传统工程合金,是由多种元素以等摩尔或近等摩尔的比例混合,形成的以简单固溶体结构为基体的系列成分复杂合金。其中含高熔点元素的难熔高熵合金具有较高的高温强度和优异的高温抗氧化性能及耐蚀性能等突出特点,其潜在的高温应用价值引起了广泛关注。详细阐述了难熔高熵合金的研究现状及应用,根据晶体结构类型将难熔合金体系进行了分类,并对各类体系中的微观组织特征进行了概述;进而归纳总结了难熔高熵合金的各种性能,包括高强度、耐磨性、高温抗氧化性、耐蚀性能等;最后对难熔高熵合金的发展及应用前景进行了展望。  相似文献   

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